I need a scource of new curtain material for the older Graflex cameras like the RBs. The material that came out was .015 thick, and the materail I have is .008. I really don't want to try and add to the materal I have, as I have tried this, and it is a bit cludgey.

Use the .008 you have. The original thickness may have been .006. All Graflex/Graphic cameras use the same curtain material and it swells with age and as it dries out.

Too thick of a material will not roll up into the body opening at the top, bottom, or both. Too stiff a material will not move through the camera easily resulting in excessive initial tension and loss of shutter speeds._________________The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.